Introduction
In their work “Histoire naturelle des îles Canaries,” Webb and Berthelot focus on the identification of the Purpurariae Islands, a term from classical sources. According to these authors, Lanzarote and Fuerteventura correspond to the Purpurariae Islands, noted for their geographical position and their natural resources, especially orchil[1].
Identification of the Purpurariae Islands
Following the views of Gosselin and d’Anville, Webb and Berthelot argue that the Purpurariae Islands are Lanzarote and Fuerteventura. This identification is based on the interpretation of ancient texts, such as those by Pliny, which mention these islands in relation to dye production and their proximity to the African continent[1]. As the authors state: “…nous partageons l’opinion de ce savant commentateur qui, à l’exemple de d’Anville, a rapporté cette ancienne dénomination à Lancerotte et à Fortaventure”[1].
Orchil and Its Importance
A key argument for this identification is the abundance of orchil (lichen roccella EL) on Lanzarote and Fuerteventura. Webb and Berthelot cite Bory de Saint-Vincent, who believed that the dye sought in these islands was orchil, highly valued since antiquity[1]. The preparation of orchil was once a secret, but it became widespread and one of the most important products of the Canary Islands. The authors note: “L’abondance de cette plante dans les îles de Lancerotte et Fortaventure semblerait confirmer les assertions de M. Bory”[1].
Historical Testimonies and Trade Monopoly
According to the source, the Phoenicians, Carthaginians, and Massaliotes successively held the monopoly on the orchil trade, which later passed to the Romans through Mauritanian merchants. This trade was abandoned for centuries until, with the European conquest of the islands, it regained importance. Chroniclers of the Béthencourt expedition in the 15th century wrote: “/y croft une graine qui vaut beaucoup et qu’on appelle orsolle, ont-ils dit, elle ‘sert à teindre drap ou autre chose, et si cette île est une fois conquise et mise à la foi chrestienne, icelle graine sera de grand valeur au sieur du pays”[1].
Geographical Position and Historical Cartography
Webb and Berthelot also highlight the importance of Lanzarote and Fuerteventura in ancient cartography, as for centuries the zero meridian was considered to pass through these islands or El Hierro, being the westernmost point known to European navigators[1]. This strategic position contributed to their significance in Atlantic navigation and exploration.
Conclusion
The identification of Lanzarote and Fuerteventura as the Purpurariae Islands by Webb and Berthelot is based on classical sources, the abundance of orchil, and their role in the history of navigation and dye trade. Their analysis provides insight into how these natural resources shaped the perception and value of the islands over time[1].